simple implementation of the roff(7) .als (macro alias) request,

[mandoc.git] / tag.c

diff --git a/tag.c b/tag.c
index 5766d540d1f1d246dc97a7a61615f0199c835472..21ac6b32e4d3a49ae6c177969178f29d2375d475 100644 (file)
--- a/tag.c
+++ b/tag.c
@@ -1,6 +1,6 @@
-/*      $Id: tag.c,v 1.10 2015/10/13 15:53:05 schwarze Exp $    */
+/*     $Id: tag.c,v 1.18 2017/02/17 14:31:52 schwarze Exp $ */
 /*
- * Copyright (c) 2015 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2015, 2016 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -31,12 +31,14 @@
 #include "tag.h"
 
 struct tag_entry {
-       size_t   line;
+       size_t  *lines;
+       size_t   maxlines;
+       size_t   nlines;
        int      prio;
        char     s[];
 };
 
-static void     tag_signal(int);
+static void     tag_signal(int) __attribute__((__noreturn__));
 
 static struct ohash     tag_data;
 static struct tag_files         tag_files;
@@ -50,10 +52,30 @@ static struct tag_files      tag_files;
 struct tag_files *
 tag_init(void)
 {
+       struct sigaction         sa;
        int                      ofd;
 
        ofd = -1;
        tag_files.tfd = -1;
+       tag_files.tcpgid = -1;
+
+       /* Clean up when dying from a signal. */
+
+       memset(&sa, 0, sizeof(sa));
+       sigfillset(&sa.sa_mask);
+       sa.sa_handler = tag_signal;
+       sigaction(SIGHUP, &sa, NULL);
+       sigaction(SIGINT, &sa, NULL);
+       sigaction(SIGTERM, &sa, NULL);
+
+       /*
+        * POSIX requires that a process calling tcsetpgrp(3)
+        * from the background gets a SIGTTOU signal.
+        * In that case, do not stop.
+        */
+
+       sa.sa_handler = SIG_IGN;
+       sigaction(SIGTTOU, &sa, NULL);
 
        /* Save the original standard output for use by the pager. */
 
@@ -66,9 +88,6 @@ tag_init(void)
            sizeof(tag_files.ofn));
        (void)strlcpy(tag_files.tfn, "/tmp/man.XXXXXXXXXX",
            sizeof(tag_files.tfn));
-       signal(SIGHUP, tag_signal);
-       signal(SIGINT, tag_signal);
-       signal(SIGTERM, tag_signal);
        if ((ofd = mkstemp(tag_files.ofn)) == -1)
                goto fail;
        if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1)
@@ -111,18 +130,58 @@ tag_put(const char *s, int prio, size_t line)
        size_t                   len;
        unsigned int             slot;
 
-       if (tag_files.tfd <= 0 || strchr(s, ' ') != NULL)
+       /* Sanity checks. */
+
+       if (tag_files.tfd <= 0)
+               return;
+       if (s[0] == '\\' && (s[1] == '&' || s[1] == 'e'))
+               s += 2;
+       if (*s == '\0' || strchr(s, ' ') != NULL)
                return;
+
        slot = ohash_qlookup(&tag_data, s);
        entry = ohash_find(&tag_data, slot);
+
        if (entry == NULL) {
+
+               /* Build a new entry. */
+
                len = strlen(s) + 1;
                entry = mandoc_malloc(sizeof(*entry) + len);
                memcpy(entry->s, s, len);
+               entry->lines = NULL;
+               entry->maxlines = entry->nlines = 0;
                ohash_insert(&tag_data, slot, entry);
-       } else if (entry->prio <= prio)
-               return;
-       entry->line = line;
+
+       } else {
+
+               /* Handle priority 0 entries. */
+
+               if (prio == 0) {
+                       if (entry->prio == 0)
+                               entry->prio = -1;
+                       return;
+               }
+
+               /* A better entry is already present, ignore the new one. */
+
+               if (entry->prio > 0 && entry->prio < prio)
+                       return;
+
+               /* The existing entry is worse, clear it. */
+
+               if (entry->prio < 1 || entry->prio > prio)
+                       entry->nlines = 0;
+       }
+
+       /* Remember the new line. */
+
+       if (entry->maxlines == entry->nlines) {
+               entry->maxlines += 4;
+               entry->lines = mandoc_reallocarray(entry->lines,
+                   entry->maxlines, sizeof(*entry->lines));
+       }
+       entry->lines[entry->nlines++] = line;
        entry->prio = prio;
 }
 
@@ -135,6 +194,7 @@ tag_write(void)
 {
        FILE                    *stream;
        struct tag_entry        *entry;
+       size_t                   i;
        unsigned int             slot;
 
        if (tag_files.tfd <= 0)
@@ -142,9 +202,11 @@ tag_write(void)
        stream = fdopen(tag_files.tfd, "w");
        entry = ohash_first(&tag_data, &slot);
        while (entry != NULL) {
-               if (stream != NULL)
-                       fprintf(stream, "%s %s %zu\n",
-                           entry->s, tag_files.ofn, entry->line);
+               if (stream != NULL && entry->prio >= 0)
+                       for (i = 0; i < entry->nlines; i++)
+                               fprintf(stream, "%s %s %zu\n",
+                                   entry->s, tag_files.ofn, entry->lines[i]);
+               free(entry->lines);
                free(entry);
                entry = ohash_next(&tag_data, &slot);
        }
@@ -156,7 +218,15 @@ tag_write(void)
 void
 tag_unlink(void)
 {
-
+       pid_t    tc_pgid;
+
+       if (tag_files.tcpgid != -1) {
+               tc_pgid = tcgetpgrp(tag_files.ofd);
+               if (tc_pgid == tag_files.pager_pid ||
+                   tc_pgid == getpgid(0) ||
+                   getpgid(tc_pgid) == -1)
+                       (void)tcsetpgrp(tag_files.ofd, tag_files.tcpgid);
+       }
        if (*tag_files.ofn != '\0')
                unlink(tag_files.ofn);
        if (*tag_files.tfn != '\0')
@@ -166,9 +236,13 @@ tag_unlink(void)
 static void
 tag_signal(int signum)
 {
+       struct sigaction         sa;
 
        tag_unlink();
-       signal(signum, SIG_DFL);
+       memset(&sa, 0, sizeof(sa));
+       sigemptyset(&sa.sa_mask);
+       sa.sa_handler = SIG_DFL;
+       sigaction(signum, &sa, NULL);
        kill(getpid(), signum);
        /* NOTREACHED */
        _exit(1);